Support is requested for a Keystone Symposia meeting entitled Neuroinflammation in Diseases of the Central Nervous System, organized by Richard M. Ransohoff, Christopher K. Glass and V. Hugh Perry. The meeting will be held in Taos, New Mexico from January 25-30, 2015. Neuroinflammation, the response of the central nervous system (CNS) to disturbed homeostasis, typifies all neurological diseases, including primary- inflammatory, developmental, traumatic, ischemic, neoplastic and neurodegenerative. Disease-associated neuroinflammatory responses aren't evolutionarily selected to minimize or repair tissue injury, and may be helpful, harmful or neutral. This Keystone Symposia meeting will: (i) address the developmental roles of neuroinflammatory cells including microglia and blood-brain barrier (BBB) neurovascular elements; (ii) clarify how neuroinflammatory reactions mediate host defense against neuroinvasive microbial pathogens, and also how the response to systemic inflammation affects the neuroinflammatory elements; (iii) specify critically- important neuroinflammatory cells (microglia; astrocytes; NG2+ glia; BBB), receptors (toll-like receptors; inflammasomes; cytokine receptors), signaling pathways and effector mechanisms; and (iv) identify the most salient targets of neuroinflammation (neurons; neural progenitor and stem cells; oligodendroglia) and mechanisms of injury. NINDS is most appropriate to support the meeting because the focus is on diseases of the CNS, i.e. Alzheimer's disease, ALS, encephalitis, paraneoplastic syndromes and Multiple Sclerosis, and because the basic science topics of microglial and astrocyte biology, blood-brain barrier and neuroinflammatory mechanisms, constitute a major focus of NINDS-funded research.